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1.
Food Chem ; 454: 139619, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38811285

RESUMO

In this study, we developed a hydrogel from cross-linked keratin and chitosan (KC) to remove patulin (PAT) from apple juice. We explored the potential of incorporating Lactobacillus rhamnoses into the KC hydrogel (KC-LR) and tested its effectiveness in removing PAT from simulated juice solutions and real apple juice. The KC hydrogel was developed through a dynamic disulfide cross-linking reaction. This cross-linked hydrogel network provided excellent stability for the probiotic cells, achieving 99.9 % immobilization efficiency. In simulated juice with 25 mg/L PAT, the KC and KC-LR hydrogels showed removal efficiencies of 85.2 % and 97.68 %, respectively, using 15 mg mL-1 of the prepared hydrogel at a temperature of 25 °C for 6 h. The KC and KC-LR hydrogels achieved 76.3 % and 83.6 % removal efficiencies in real apple juice systems, respectively. Notably, the encapsulated probiotics did not negatively impact the juice quality and demonstrated reusability for up to five cycles of the PAT removal process.


Assuntos
Quitosana , Sucos de Frutas e Vegetais , Hidrogéis , Queratinas , Lacticaseibacillus rhamnosus , Malus , Patulina , Quitosana/química , Malus/química , Sucos de Frutas e Vegetais/análise , Lacticaseibacillus rhamnosus/química , Hidrogéis/química , Patulina/química , Patulina/isolamento & purificação , Queratinas/química , Queratinas/isolamento & purificação , Probióticos/química , Contaminação de Alimentos/análise
2.
Food Chem ; 451: 139421, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663244

RESUMO

Patulin (PAT) is a hazardous mycotoxin frequently occurs in fruit industry. A reusable g-C3N4-SH@KG composite aerogel for PAT removal in a novel "dark adsorption-light regeneration" mode was prepared by thiol(-SH) functionalization and konjac glucomannan (KG) immobilization. The g-C3N4-SH@KG was characterized by SEM, FT-IR, XPS and UV-Vis DRS, and its PAT adsorption and photocatalytic regeneration behaviors and mechanisms were investigated. The g-C3N4-SH@KG exhibited good regeneration performance, maintaining 83% of PAT initial adsorption capacity (0.92 mg/g) after 5 "adsorption-regeneration" cycles. The adsorption process was endothermic and spontaneous. •OH and h+ generated by photocatalysis were the main substances that degraded PAT into two products and regenerated -SH. The g-C3N4-SH@KG could effectively remove PAT without negative impact on juice quality. The study provided a new strategy for the regeneration of thiol-functionalized PAT adsorbents, and a new idea for the application of non-selective photocatalysis in the control of food contaminations.


Assuntos
Sucos de Frutas e Vegetais , Malus , Mananas , Patulina , Malus/química , Mananas/química , Sucos de Frutas e Vegetais/análise , Patulina/química , Patulina/isolamento & purificação , Adsorção , Contaminação de Alimentos/análise , Catálise , Géis/química
3.
Food Chem ; 358: 129817, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33940302

RESUMO

In this paper, a green and inexpensive air-assisted natural deep eutectic solvent-based solidified homogeneous liquid phase microextraction procedure was optimized for extraction of patulin in fruit juice and dried fruit samples using experimental design prior to its spectrophotometric determination. Four different natural deep eutectic solvent were prepared and applied to ensure efficient, and selective extraction of patulin. The significant variables including Zn(II) amount, cooling time, pH and amount of natural deep eutectic solvent were optimized by using central composite design. Under optimized conditions, working range was 10-750 µg L-1 with 0.9996 of correlation coefficient. Detection limit and preconcentration factor were 3.5 µg L-1 and 150, respectively. The repeatability and reproducibility precision were in the range of 3.2-4.6% and 4.3-5.6% respectively. Recoveries ranging from 94% to 104% proved the accuracy of the method. The optimized method was successfully applied to the extraction and identification of patulin in the selected samples.


Assuntos
Sucos de Frutas e Vegetais , Frutas/química , Microextração em Fase Líquida/métodos , Patulina/isolamento & purificação , Química Computacional , Química Verde , Concentração de Íons de Hidrogênio , Limite de Detecção , Reprodutibilidade dos Testes , Projetos de Pesquisa , Solventes/química , Espectrofotometria Ultravioleta , Fatores de Tempo
4.
Food Chem ; 348: 129046, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33508606

RESUMO

Biodegradation based on microbial enzymes is considered to be one of the promising ways for controlling patulin contamination. However, few patulin degrading enzymes have been isolated and characterized until now. Here, a short-chain dehydrogenase/reductase (SDR) gene, CgSDR, was cloned from a yeast strain Candida guilliermondii, and expressed in Escherichia coli. The expression of CgSDR conferred a strong patulin tolerance and degradation ability to E. coli, and purified CgSDR could transform patulin into E-ascladiol in vitro with NADPH as a coenzyme. Moreover, addition of CgSDR at 150 µg/mL could reduce 80% of patulin in apple juice and the biodegradation process did not affect the quality of the apple juice. A molecular docking analysis and site-directed mutagenesis indicated that CgSDR might interact with patulin via VAL188 as an active binding sites. The findings provide new insights for developing enzymic formulations for mycotoxin detoxification in fruit derived products.


Assuntos
Sucos de Frutas e Vegetais/análise , Malus/química , Patulina/metabolismo , Redutases-Desidrogenases de Cadeia Curta/metabolismo , Biodegradação Ambiental , Contaminação de Alimentos/análise , Simulação de Acoplamento Molecular , Patulina/isolamento & purificação , Saccharomycetales/enzimologia
5.
J Sci Food Agric ; 101(5): 1767-1771, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32888337

RESUMO

BACKGROUND: Patulin is a mycotoxin that mainly contaminates apple juice, which is a typical high sugar matrix. Many different adsorbents have been utilized to develop a sample pretreatment method to minimize the matrix interference from apple juice. RESULTS: A simple and reliable extraction method for the determination of patulin in apple juice has been developed. The sample preparation involves a simple one-step cleanup procedure using amine-functionalized polymeric solid-phase extraction cartridges (Retain AX) that effectively remove interferences and facilitate the quantification. Isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) was employed to minimize the matrix effect and ensure reliable results. The limit of detection was as low as 0.2 µg kg-1 , which was satisfactory with regard to current European, US, and Chinese legislation. Matrix-matched linearity (r2 = 0.9997) was established in the range of 1-400 µg kg-1 . Recovery was performed in samples spiked at three levels, and results were between 97.2% and 100.2%. CONCLUSION: The results indicated that, with one-step cleanup, the matrix effect was negligible and sensitivity was satisfactory. Our work provided a simple and reliable method for patulin detection in apple juice and is also very promising in routine quality control. © 2020 Society of Chemical Industry.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Sucos de Frutas e Vegetais/análise , Malus/química , Patulina/análise , Patulina/isolamento & purificação , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Aminas/química , Contaminação de Alimentos/análise , Frutas/química , Extração em Fase Sólida/instrumentação
6.
Food Chem ; 338: 127785, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32798825

RESUMO

Patulin (PAT) contaminant causes severe food safety issue throughout apple industry. Although adsorption is the feasible approach to remove PAT, the limited adsorption capacity and separation difficulty of most adsorbent is the major drawback that remains to be overcome. Here GO-SH doped aerogel was prepared and used for removal PAT from apple juice. The intrinsic porous of the aerogel and abundant active sites including -COOH, -NH2 and -SH offered the PAT adsorption capacity of 24.75 µg/mg that superior to most reported adsorbents. Furthermore, it could reduce 89 ± 1.23% PAT in real apple juice without juice quality deterioration and cytotoxicity. Importantly, the aerogel with good mechanical strength and structure stability could endure the complex juice solution so that there was no any residue after convenient separation of the aerogel, which proved that the proposed aerogel was a promising adsorbent to be applied to apple juice industry for PAT removal.


Assuntos
Sucos de Frutas e Vegetais/análise , Grafite/química , Malus/química , Patulina/química , Patulina/isolamento & purificação , Enxofre/química , Adsorção , Contaminação de Alimentos/análise , Géis
7.
Artigo em Inglês | MEDLINE | ID: mdl-32305710

RESUMO

A highly efficient and selective method was successfully developed by using magnetic molecularly imprinted polymers (MMIPs) combined with high performance liquid chromatography (HPLC) to quickly determine patulin (PAT) in juice. MMIPs was prepared by surface imprinting method using Fe3O4 nanoparticles as supporter, 2-oxindole as virtual template, (3-Aminopropyl) triethoxysilane (APTES) as functional monomer and tetraethyl orthosilicate (TEOS) as crosslinking agent. The structure of the product was characterized by vibrating sample magnetometer (VSM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The results showed that MMIP with a particle size of about 450 nm was successfully prepared, the imprinted molecular layer accounted for about 11.6% of the total mass, and the saturation magnetization was about 6.82 emu/g. The maximum adsorption capacities (Qmax) of kinetic and thermodynamic adsorption experiments were 1.97 mg/g and 4.241 mg/g, respectively. The adsorption process was highly selective and fitted well with the pseudo-second-order model. Langmuir model demonstrated that the binding sites were evenly distributed on the surface of the MMIPs. Scatchard analysis showed that MMIPs had two types of binding sites with Qmax of 4.53 mg/g and 5.73 mg/g, respectively. In the actual sample application, the limit of detection (LOD) and the limit of quantification (LOQ) were 3 µg/kg and 10 µg/kg. And the recovery rate of the sample was 86.44-95.50%. MMIPs possessed excellent applicability with stability of 1.11-3.16% and accuracy of 0.63-1.94%. These results indicated that MMIPs had good performance in separating PAT and was suitable for determining PAT in actual samples.


Assuntos
Sucos de Frutas e Vegetais/análise , Magnetismo/métodos , Polímeros Molecularmente Impressos/química , Patulina/isolamento & purificação , Extração em Fase Sólida/métodos , Adsorção , Cromatografia Líquida de Alta Pressão , Contaminação de Alimentos/análise , Magnetismo/instrumentação , Nanopartículas de Magnetita/química , Patulina/química , Extração em Fase Sólida/instrumentação , Espectroscopia de Infravermelho com Transformada de Fourier
8.
J Chromatogr A ; 1615: 460751, 2020 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-31864724

RESUMO

In this study, a novel magnetic molecularly imprinted polymer (MMIP) was prepared by surface imprinting technology using 2-oxin and 6-HNA as dual virtual templates and 4-vinyl pyridine (4-VP) as the functional monomer for extraction of patulin (PAT) from the surface of magnetic nanoparticles. MMIPs were characterized by fourier transformed infrared (FT-IR) spectroscopy, X-ray diffraction, and vibrating sample magnetometry. The results showed that the molecularly imprinted polymer (MIP) was successfully coupled with magnetic nanoparticles and could be used as a magnetic selective recognition material. Moreover, MMIPs have a greater adsorption capacity for PAT than conventional MIPs. The magnetic dispersion solid-phase extraction procedure was optimized and then combined with liquid chromatography-tandem mass spectrometry (MDSPE-LC-MS/MS) for detection of PAT in juice samples. The method showed excellent analytical performance in terms of linearity (ranged between 0.5 µg L-1 and 100 µg L-1with correlation coefficients (r) higher than 0.999) and limit of detection (LOD) (0.1 µg L-1, S/N = 3). At three spiking concentrations (1, 10, and 50 µg L-1), the mean recoveries were ranged between 79.4% and 97.9% with relative standard deviations (RSDs) < 4.7% (n = 3).


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Nanopartículas/química , Patulina/análise , Polímeros/síntese química , Adsorção , Cromatografia Líquida , Limite de Detecção , Fenômenos Magnéticos , Impressão Molecular , Patulina/isolamento & purificação , Extração em Fase Sólida , Espectroscopia de Infravermelho com Transformada de Fourier , Espectrometria de Massas em Tandem , Difração de Raios X
9.
Molecules ; 24(15)2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31366160

RESUMO

The identification and characterization of fungal commensals of the human gut (the mycobiota) is ongoing, and the effects of their various secondary metabolites on the health and disease of the host is a matter of current research. While the neurons of the central nervous system might be affected indirectly by compounds from gut microorganisms, the largest peripheral neuronal network (the enteric nervous system) is located within the gut and is exposed directly to such metabolites. We analyzed 320 fungal extracts and their effect on the viability of a human neuronal cell line (SH-SY5Y), as well as their effects on the viability and functionality of the most effective compound on primary enteric neurons of murine origin. An extract from P. coprobium was identified to decrease viability with an EC50 of 0.23 ng/µL in SH-SY5Y cells and an EC50 of 1 ng/µL in enteric neurons. Further spectral analysis revealed that the effective compound was patulin, and that this polyketide lactone is not only capable of evoking ROS production in SH-SY5Y cells, but also diverse functional disabilities in primary enteric neurons such as altered calcium signaling. As patulin can be found as a common contaminant on fruit and vegetables and causes intestinal injury, deciphering its specific impact on enteric neurons might help in the elaboration of preventive strategies.


Assuntos
Micotoxinas/toxicidade , Neurônios/efeitos dos fármacos , Patulina/toxicidade , Penicillium/química , Animais , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Misturas Complexas/química , Sistema Nervoso Entérico/citologia , Sistema Nervoso Entérico/efeitos dos fármacos , Sistema Nervoso Entérico/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Micotoxinas/química , Micotoxinas/isolamento & purificação , Neurônios/citologia , Neurônios/metabolismo , Patulina/química , Patulina/isolamento & purificação , Cultura Primária de Células , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-31357106

RESUMO

A molecularly imprinted polymer (MIP) with specific adsorption for patulin was successfully polymerized by precipitation polymerization using 2-oxindole (2-oxin) and 6-hydroxynicotinic acid (6-HNA) as dummy template molecules, methylacrylic acid (MAA) as a functional monomer, trimethylolpropane trimethacrylate (TRIM) as a crosslinker, 2,2-azobis-(2-methylpropionitrile) (AIBN) as a initiator, and methanol as a porogen solvent. The molecularly imprinted solid phase extraction (MI-SPE) column was prepared using the polymer as a sorbent and applied for the selective extraction of patulin from real samples. The results showed that the MI-SPE method had high selectivity and specific adsorption towards patulin with mean recoveries ranged between 81.3% and 106.3% and a relative standard deviation (RSD) < 4.5%. Additionally, the developed MI-SPE method coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) exhibited good linearity in the range of 1-100 ng mL-1 with correlation coefficients (R2) >0.998. The limits of detection (LODs, S/N = 3) were 0.05-0.2 ng g-1, and the limits of quantification (LOQs, S/N = 10) were 0.2-0.5 ng g-1. The developed method showed a better purification and higher patulin recovery for real samples than the quick, easy, cheap, effective, rugged, safe "QuEChERS" method.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Contaminação de Alimentos/análise , Patulina/análise , Patulina/isolamento & purificação , Extração em Fase Sólida/métodos , Espectrometria de Massas em Tandem/métodos , Adsorção , Impressão Molecular , Mutagênicos/análise , Mutagênicos/isolamento & purificação , Polímeros/síntese química , Polímeros/química , Extração em Fase Sólida/instrumentação
11.
Anal Chem ; 91(6): 4116-4123, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30793880

RESUMO

An innovative approach based on a surface functional monomer-directing strategy for the construction of a sensitive and selective molecularly imprinted electrochemical sensor for patulin recognition is described. A patulin imprinted platinum nanoparticle (PtNP)-coated poly(thionine) film was grown on a preformed thionine tailed surface of PtNP-nitrogen-doped graphene (NGE) by electropolymerization, which provided high capacity and fast kinetics to uptake patulin molecules. Thionine acted not only as a functional monomer for molecularly imprinted polymer (MIP), but also as a signal indicator. Enhanced sensitivity was obtained by combining the excellent electric conductivity of PtNPs, NGE, and thionine with multisignal amplification. The designed sensor displayed excellent performance for patulin detection over the range of 0.002-2 ng mL-1 (R2 = 0.995) with a detection limit of 0.001 ng mL-1 for patulin. In addition, the resulting sensor showed good stability and high repeatability and selectivity. Furthermore, the feasibility of its applications has also been demonstrated in the analysis of real samples, providing novel tactics for the rational design of MIP-based electrochemical sensors to detect a growing number of deleterious substances.


Assuntos
Cromatografia de Afinidade/métodos , Técnicas Eletroquímicas/métodos , Sucos de Frutas e Vegetais/análise , Impressão Molecular/métodos , Mutagênicos/análise , Patulina/análise , Fenotiazinas/química , Técnicas Biossensoriais , Limite de Detecção , Malus/química , Mutagênicos/química , Nanopartículas/química , Patulina/química , Patulina/isolamento & purificação , Vitis/química
12.
Food Chem ; 270: 1-9, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30174021

RESUMO

Patulin (PAT) is one of the most common toxic contaminants of apple juice, which causes severe food safety issues throughout the apple industry. In order to remove PAT efficiently, a metal-organic framework-based adsorbent (UiO-66(NH2)@Au-Cys) was successfully synthesized and used for PAT removal from juice-pH simulation solution and real apple juice. Batch adsorption experiments were systematically performed to study the adsorption behavior for PAT. The results showed that adsorption process could be well described by the Pseudo-second order model and Freundlich isotherm model. The maximum adsorption capacity (4.38 µg/mg) was 10 times higher than the microbe-based biosorbents. Thermodynamic investigation demonstrated that adsorption process was spontaneous and endothermic. Furthermore, no marked cytotoxicity on NIH 3T3 cell lines was observed when the concentration of the adsorbent was lower than 10 µg/mL. Therefore, UiO-66(NH2)@Au-Cys is a potential adsorbent for PAT removal from apple juice with little quality changes.


Assuntos
Manipulação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Malus/química , Patulina/química , Adsorção , Cisteína , Estruturas Metalorgânicas , Patulina/isolamento & purificação
13.
J Hazard Mater ; 366: 413-422, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30554087

RESUMO

Patulin is a naturally produced toxin having potential carcinogenic properties. It is mainly produced by species of Penicillium growing on fruits, especially on apples. Detoxification of patulin, therefore, is very important for providing food safety. In this study, sulfhydryl-terminated, silica coated iron oxide beads were investigated as a multi-use sorbents for effective recovery of patulin from apple juice. The effect of beads amount, contact time, pH and temperature were evaluated for high adsorption capacity and the results showed maximum adsorption capacity at a reaction condition of 1.5 mg of beads for 4 h incubation at pH 7.2 and 25 °C. These sorbents were highly effective both in aqueous solution and apple juice with adsorption efficiencies of 99% and 71.25%, respectively. Adsorption process was explained by Langmuir isotherm model with pseudo-second order kinetic model. Thermodynamic parameters described spontaneous adsorption of patulin onto beads with high feasibility and preferences. The reusability of sulfhydryl coated magnetic beads was shown for at least four times without any significant decreases in efficiency. Results showed that this sorbent had potential for removal of patulin from apple juice without any negative effects on final quality parameters, Brix, color, clarity, total sugar and titratable acidity.


Assuntos
Bebidas/análise , Magnetismo , Malus/química , Patulina/isolamento & purificação , Compostos de Sulfidrila/química , Adsorção , Cinética , Soluções , Termodinâmica , Água/química
14.
J Appl Microbiol ; 126(4): 1149-1160, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30520191

RESUMO

AIMS: The aim of this study was to evaluate the elimination of patulin (PAT) by Lactobacillus plantarum ATCC 8014 from artificially contaminated apple juice and its dependence on prebiotic, citric acid and ascorbic acid content. METHODS AND RESULTS: A central composite design was used for studying each of the three factors at five levels to find the optimum concentrations. The results showed that inserting 2·3% (w/v) fructooligosaccharide, 213 mg l-1 ascorbic acid and 1·4 g l-1 citric acid to apple juice with inoculating 3·6 × 1011 CFU per ml, L. plantarum improved the efficiency of PAT removal to 95·91% during 6 weeks cold storage. SDS-PAGE of cell surface proteins of probiotics revealed that surface layer proteins have an important role in PAT removal from apple juice. No significant difference was observed in the flavour and colour of the optimized synbiotic apple juice and in the control sample until 3 weeks of cold storage. CONCLUSION: Lactobacillus plantarum ATCC 8014 is capable of PAT removal from artificially contaminated synbiotic apple juice. SIGNIFICANCE AND IMPACT OF THE STUDY: Synbiotic apple juice artificially contaminated with PAT will be safe for consumers after the first day of probiotic inoculation; and surface layer proteins of probiotic cells are responsible for PAT removal.


Assuntos
Microbiologia de Alimentos , Sucos de Frutas e Vegetais/microbiologia , Lactobacillus plantarum/fisiologia , Malus , Patulina/isolamento & purificação , Contaminação de Alimentos/análise , Contaminação de Alimentos/prevenção & controle , Sucos de Frutas e Vegetais/análise , Patulina/metabolismo , Probióticos/metabolismo , Simbióticos/análise
15.
Food Chem ; 257: 1-6, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-29622184

RESUMO

Quick and simple analytical methodology has been developed for the measurement of patulin in apple juice by combining single-drop liquid-liquid-liquid microextraction with isotope dilution ultra-high performance liquid chromatography-mass spectrometry. After systematic parameters optimization, the whole sample pretreatment only consisted of single extraction that consumed 1.5 mL ethyl acetate. While, other methods usually needed complicated pretreatment, including extraction, purification, evaporation and redissolution. This sample pretreatment method could greatly lower the interferences from sugar-rich matrix, and the limit of detection was 0.5 µg/L and limit of quantification was 2 µg/L in apple juice. Moreover, linear range covered three orders of magnitude from 2 to 2000 µg/L. The proposed method is promising for patulin extraction and detection in apple juice, which will opens a new perspective in the enrichment of trace contaminations in high sugar complex matrix.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Análise de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Microextração em Fase Líquida/métodos , Malus/química , Espectrometria de Massas/métodos , Patulina/análise , Contaminação de Alimentos/análise , Patulina/isolamento & purificação
16.
Molecules ; 23(3)2018 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-29534536

RESUMO

Lung cancer is the most lethal form of cancer in the world. Its development often involves an overactivation of the nuclear factor kappa B (NF-κB) pathway, leading to increased cell proliferation, survival, mobility, and a decrease in apoptosis. Therefore, NF-κB inhibitors are actively sought after for both cancer chemoprevention and therapy, and fungi represent an interesting unexplored reservoir for such molecules. The aim of the present work was to find naturally occurring lung cancer chemopreventive compounds by investigating the metabolites of Penicillium vulpinum, a fungus that grows naturally on dung. Penicillium vulpinum was cultivated in Potato Dextrose Broth and extracted with ethyl acetate. Bioassay-guided fractionation of this extract was performed by measuring NF-κB activity using a HEK293 cell line transfected with an NF-κB-driven luciferase reporter gene. The mycotoxin patulin was identified as a nanomolar inhibitor of TNF-α-induced NF-κB activity. Immunocytochemistry and Western blot analyses revealed that its mechanism of action involved an inhibition of p65 nuclear translocation and was independent from the NF-κB inhibitor α (IκBα) degradation process. Enhancing its interest in lung cancer chemoprevention, patulin also exhibited antiproliferative, proapoptotic, and antimigration effects on human lung adenocarcinoma cells through inhibition of the Wnt pathway.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Pulmonares/metabolismo , Patulina/farmacologia , Penicillium/química , Fator de Necrose Tumoral alfa/metabolismo , Células A549 , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Patulina/química , Patulina/isolamento & purificação , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo
17.
J Sep Sci ; 40(23): 4599-4609, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28986945

RESUMO

Reaching trace amounts of mycotoxin contamination requires sensitive and selective analytical tools for their determination. Improving the selectivity of sample pretreatment steps covering new and modern extraction techniques is one way to achieve it. Molecularly imprinted polymers as selective sorbent for extraction undoubtedly meet these criteria. The presented work is focused on the hyphenation of on-line molecularly imprinted solid-phase extraction with a chromatography system using a column-switching approach. Making a critical comparison with a simultaneously developed off-line extraction procedure, evaluation of pros and cons of each method, and determining the reliability of both methods on a real sample analysis were carried out. Both high-performance liquid chromatography methods, using off-line extraction on molecularly imprinted polymer and an on-line column-switching approach, were validated, and the validation results were compared against each other. Although automation leads to significant time savings, fewer human errors, and required no handling of toxic solvents, it reached worse detection limits (15 versus 6 µg/L), worse recovery values (68.3-123.5 versus 81.2-109.9%), and worse efficiency throughout the entire clean-up process in comparison with the off-line extraction method. The difficulties encountered, the compromises made during the optimization of on-line coupling and their critical evaluation are presented in detail.


Assuntos
Impressão Molecular , Patulina/isolamento & purificação , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Polímeros , Reprodutibilidade dos Testes
18.
Biosens Bioelectron ; 98: 299-304, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28697441

RESUMO

In this paper, molecular imprinting technique was applied to the electrochemical sensor. We used 2-oxindole as dummy template, ρ-Aminothiophenol (ρ-ATP) as functional monomers, combined with the high sensitivity of electrochemical detection, to achieve a specific and efficient detection of patulin in fruit juice. In addition, carbon dots and chitosan were used as the modifying material to improve electron-transfer rate, expand the electroactive surface of glassy carbon electrode and enhance strength of the signal. The Au-S bond and hydrogen bond were employed to complete the assembly of the ρ-ATP and 2-oxindole on the surface of the electrode. Then, polymer membranes were formed by electropolymerization in a polymer solution containing ρ-ATP, HAuCl4, tetrabutylammonium perchlorate (TBAP) and the template molecule 2- oxindole. After elution, the specific cavity can adsorb the target patulin. Cyclic voltammetry (CV) and differential pulse voltammetry (DPV) measurements were performed to monitor the electropolymerization process and its optimization. Transmission electron microscopy (TEM), Scanning electron microscopy (SEM) and Atomic force microscopy (AFM) analyses were used for characterization. This was the first time that the molecularly imprinted polymer (MIP) technology combined with carbon dots, chitosan and Au nanoparticles modification and was applied in the electrochemical detection of patulin. The linear response range of the MIP sensor was from 1 × 10-12 to 1 × 10-9molL-1 and the limit of detection (LOD) was 7.57 × 10-13molL-1. The sensor had a high-speed real-time detection capability, low sample consumption, high sensitivity, low interference, good stability and could become a new promising method for the detection of patulin.


Assuntos
Técnicas Biossensoriais/métodos , Nanopartículas Metálicas/química , Patulina/isolamento & purificação , Carbono/química , Quitosana/química , Técnicas Eletroquímicas/métodos , Indóis/química , Limite de Detecção , Microscopia Eletrônica de Varredura/métodos , Impressão Molecular , Oxindóis
19.
Int J Food Microbiol ; 254: 25-35, 2017 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-28511111

RESUMO

Penicillium frequentans (Pf909) reduces brown rot caused by Monilinia spp. in stone fruit. The registration of a microbial biocontrol agent in Europe requires information on the risks and safety of a biological product. This study focused on the impact of the physical environment on Pf909 survival and growth, Pf909 mycotoxin production on fruit surface, and the Pf909 resistance to commercial antifungal compounds used in animal and human medicine. The effect of temperature (4 to 37°C), water activity (0.999 to 0.900), pH (3 to 11), light intensity (0, 90 and 180lm) and photoperiod (0/24, 12/12, 16/8, 24/0; light/dark) on mycelial growth and sporulation of Pf909 were monitored for 10days in vitro on culture medium. Antifungal activity of antifungal compounds on mycelial growth of Pf909 was also measured by a quantitative micro spectrophotometric assay after 72h of incubation. The presence or absence of four non-volatile mycotoxins (patulin, penicillic acid, ochratoxin A and citrinin) on nectarine surfaces treated with Pf909 was determined by HPLC. Growth rate was significantly influenced by water activity, temperature and light exposure conditions. Pf909 showed maximum growth and sporulation at 22°C and 25°C, in wet conditions (0.999 water activity), with a pH5.6 to 9, and in darkness or a short light photoperiod. Our results showed all antifungal compounds used reduced significantly Pf909 mycelial growth at tested commercial doses. HPLC data analysis showed that 7days after biofungicide (Pf909) application there were no mycotoxin products on the surface of nectarine. Finally, no phylogenetic relationship has been shown among Pf909 and other species of Penicillium that produce mycotoxins. In conclusion, from an ecological point of view, Pf909 would establish and survive actively over a broad range of climatic conditions. The probability of risks to human and animal health is considered very low.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Agentes de Controle Biológico/efeitos adversos , Agentes de Controle Biológico/farmacologia , Inocuidade dos Alimentos/métodos , Frutas/microbiologia , Micotoxinas/isolamento & purificação , Penicillium/metabolismo , Prunus persica/microbiologia , Animais , Citrinina/isolamento & purificação , Europa (Continente) , Micélio/crescimento & desenvolvimento , Ocratoxinas/isolamento & purificação , Patulina/isolamento & purificação , Ácido Penicílico/isolamento & purificação , Filogenia
20.
PLoS One ; 10(11): e0143431, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26581099

RESUMO

The purpose of this study was to identify the key factors involved in patulin adsorption by heat-inactivated lactic acid bacteria (LAB) cells. For preventing bacterial contamination, a sterilization process was involved in the adsorption process. The effects of various physical, chemical, and enzymatic pre-treatments, simultaneous treatments, and post-treatments on the patulin adsorption performances of six LAB strains were evaluated. The pre-treated cells were characterized by scanning electron microscopy (SEM). Results showed that the removal of patulin by viable cells was mainly based on adsorption or degradation, depending on the specific strain. The adsorption abilities were widely increased by NaOH and esterification pre-treatments, and reduced by trypsin, lipase, iodate, and periodate pre-treatments. Additionally, the adsorption abilities were almost maintained at pH 2.2-4.0, and enhanced significantly at pH 4.0-6.0. The effects of sodium and magnesium ions on the adsorption abilities at pH 4 were slight and strain-specific. A lower proportion of patulin was released from the strain with higher adsorption ability. Analyses revealed that the physical structure of peptidoglycan was not a principal factor. Vicinal OH and carboxyl groups were not involved in patulin adsorption, while alkaline amino acids, thiol and ester compounds were important for patulin adsorption. Additionally, besides hydrophobic interaction, electrostatic interaction also participated in patulin adsorption, which was enhanced with the increase in pH (4.0-6.0).


Assuntos
Ácido Láctico/metabolismo , Lactobacillaceae/metabolismo , Patulina/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Lactobacillaceae/ultraestrutura , Cloreto de Magnésio/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Cloreto de Sódio/farmacologia , Solventes
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